Airworthiness Directive · Amendment 39-21570 · Time limits/maintenance checks
Pilatus Aircraft Ltd. Airplanes
This AD applies to Pilatus Aircraft Ltd. Model PC-6, PC-6-H1, PC-6-H2, PC-6/350, PC-6/350-H1, PC-6/350-H2, PC-6/A, PC-6/A-H1, PC-6/A-H2, PC-6/B-H2, PC-6/B1-H2, PC-6/B2-H2, PC-6/B2-H4, PC-6/C-H2, and PC-6/C1-H2 airplanes, all serial numbers, certificated in any category.
Note 1 to paragraph (c): These airplanes may also be identified as Fairchild Republic Company airplanes, Fairchild Industries airplanes, Fairchild Heli Porter airplanes, or Fairchild-Hiller Corporation airplanes.
The FAA is superseding Airworthiness Directive (AD) 2014-25-04 for all Pilatus Aircraft Ltd. (Pilatus) Model PC-6, PC-6-H1, PC-6-H2, PC-6/350, PC-6/350-H1, PC-6/350-H2, PC-6/A, PC-6/A-H1, PC-6/A-H2, PC-6/ B-H2, PC-6/B1-H2, PC-6/B2-H2, PC-6/B2-H4, PC-6/C-H2, and PC-6/C1-H2 airplanes. AD 2014-25-04 required incorporating revised airworthiness limitations into the aircraft maintenance manual (AMM) for your FAA- approved maintenance program. This AD requires incorporating new airworthiness limitations and an eddy current inspection of each fuselage wing fitting if an earlier version of the service information was accomplished. This AD was prompted by a determination that the new life limits, revised airworthiness limitations, and new inspection procedures are necessary. The FAA is issuing this AD to address the unsafe condition on these products.
Unless already done, before further flight, comply with the actions specified in paragraphs (f)(1) through (3) of this AD.
(1) For Models PC-6/B2-H2 and PC-6/B2-H4 airplanes, revise the airworthiness limitations section (ALS) of the existing maintenance manual or instructions for continued airworthiness (ICA) for your airplane as follows:
(i) Replace Section 04-00-00 with Section 04-00-00, Airworthiness Limitations, of Chapter 04, Airworthiness Limitations, of the Pilatus PC-6 Aircraft Maintenance Manual Document No. 01975, Revision 30, dated October 30, 2020.
(ii) Add (or replace, if applicable) Section 53-00-01, Fuselage Wing Fittings—Inspection/Check, of the Pilatus PC-6 Aircraft Maintenance Manual Document No. 01975, Revision 30, dated October 30, 2020.
(iii) Add Section 57-00-03, Wing to Fuselage Fittings—Inspection/Check, of the Pilatus PC-6 Aircraft Maintenance Manual Document No. 01975, Revision 29, dated February 28, 2020.
(2) For all airplanes specified in paragraph (c) of this AD except Models PC-6/B2-H2 and PC-6/B2-H4 airplanes, revise the ALS of the existing maintenance manual or ICA for your airplane as follows:
(i) Replace the ALS with the Airworthiness Limitations Section of Pilatus PC-6 Airworthiness Limitations Document No. 02334, Revision 10, dated October 30, 2020.
(ii) Add (or replace, if applicable) Appendix K, Fuselage Wing Fittings—Inspection/Check, of Pilatus PC-6 Airworthiness Limitations Document No. 02334, Revision 10, dated October 30, 2020.
(iii) Add Appendix L, Wing to Fuselage Fittings—Inspection/Check, of Pilatus PC-6 Airworthiness Limitations Document No. 02334, Revision 9, dated March 6, 2020.
(3) For all airplanes specified in paragraph (c) of this AD, after revising the ALS as required by paragraphs (f)(1) and (2) of this AD, remove from service each part that has reached or exceeded its new life limit.
(1) For airplanes with a bush part number (P/N) 6100.0020.01 that has been bonded as specified in Section 53-00-01, Fuselage Wing Fittings—Inspection/Check, of Pilatus PC-6 Aircraft Maintenance Manual Document No. 01975, Revision 29, dated February 28, 2020; or Appendix K, Fuselage Wing Fittings—Inspection/Check, of Pilatus PC-6 Airworthiness Limitations Document No. 02334, Revision 9, dated March 6, 2020: Within 50 hours time-in-service (TIS) after the effective date of this AD, perform a visual and eddy current inspection of each fuselage wing fitting on fuselage Frame 3, remove bush P/N 6100.0020.01 from service, and install a new (zero hours TIS) bush P/N 6100.0020.01 into Frame 3 with grease by using the procedures specified in paragraph (f)(1)(ii) or (f)(2)(ii) of this AD, as applicable to your airplane.
(2) Unless already done, within 1,100 hours TIS after the effective date of this AD or within 12 months after the effective date of this AD, whichever occurs first, perform an eddy current inspection of each fuselage wing fitting and each wing-to-fuselage fitting using the procedures specified in paragraphs (f)(1)(ii) and (iii) of this AD, or paragraphs (f)(2)(ii) and (iii) of this AD, as applicable to your airplane. Thereafter, repeat the eddy current inspection of each fuselage wing fitting and each wing-to-fuselage fitting at the intervals specified in the ALS identified in paragraph (f)(1)(i) or (f)(2)(i), as applicable to your airplane.
After the ALS has been revised as required by paragraph (f) of this AD, no alternative inspection intervals or procedures may be approved, except as provided in paragraph (i) of this AD.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
